The present invention relates to an electronic analog timepiece, and in particular, to an electronic timepiece having multifunction indicators such as chronograph indication, timer indication and elapsed time indication.
To meet consumer demand, electronic analog timepieces such as watches have been manufactured having multifunctions such as chronograph, alarm, elapsed time and the like. Multifunction electronic analog watches are known from Japanese Patent Laid Open Nos. 286783/86 and 294388/86 and Japanese Utility Model Laid Open No. 26191/86 and include a small second hand, alarm hour/minute hands and other analog indicators in addition to twelve hour second, hour and minute hands. A small window for exclusive multifunction use is provided at arbitrary positions on the watch face for example, at the six o'clock watch face position, or some other position to indicate a special non-time keeping function such as the alarm time. Additionally an auxiliary stem, in addition to the normally provided stem, and a switch for switching into multifunction modes are required. The addition of multifunction indicators, stems and switches makes it possible to provide a variety of watch designs to cope with diversified consumer preferences and requirements.
These prior art multifunction electronic analog watches have been less than satisfactory. An individual watch movement structure and integrated circuit ("IC") for driving the structure are required for each combination of functions to be added. Accordingly, the movement structure and positioning of parts within the watch structure must be changed in accordance with the positioning of function indicators and due to the addition or reduction of functions and specification changes. Accordingly, the IC must be changed to match each new watch embodiment. Accordingly, manufacturers are forced to produce a variety of multifunction watches in small quantities to comply with consumer requirements as well as to provide a large variation in watch design function.
To vary the prior art multifunction electronic analog watches requires providing a number of dies, additional manual labor for changing the parts for each new watch model, changing the IC mask in accordance with each IC change as well as the time and work required for each design change resulting in a high cost for each multifunction electronic watch. Additionally, to design a multifunction watch with a redundancy which allows the disposition of a variety of parts and IC constructed to satisfy various embodiments of a single model electronic watch leads to a large watch size as well as increasing the cost of each watch.
Additionally, development of such ICs requires a relatively long period of time to design. It is therefore difficult to accommodate current market needs due to the long lead time required. Modification to the IC must be made on a large scale when adding new functions to the watch or otherwise changing the manufacturing specifications. Such modifications can require the IC to be totally redesigned. A single IC is also not able to cope with functional variations in the watch. Consequently, the constant changing diversified needs of the consumer cannot be satisfied by conventional multifunctional analog electronic watches.
The prior art multifunction electronic analog watches are also provided with an alarm. The alarm operates in an alarm ringing mode and an alarm non-ringing mode. In the alarm ringing mode, a preset alarm set time is retained even after the alarm has been activated. The alarm also rings a predetermined period of time after the initial occurrence of the alarm ringing, such as, when the alarm set time again coincides with a current time. For example, this would occur each 12 hours on a conventional multifunction analog electronic watch. In the prior art, to prevent the successive ringing of the alarm once the alarm has occurred, the alarm must be put into a mode which prohibits alarm activation through some switch operation or the like. Additionally, when resetting the alarm from the ringing prohibition state, the ringing prohibition state must be released thus involving a complicated operation. Accordingly, when the alarm is to be set in its alarm activated mode for two distinct alarm times, for example, if the alarm is to be activated a first time and then ten minutes in the future, the user of the watch must calculate the time in which the alarm is to be reactivated, add that time to the current time and then set the alarm for this second activation time, a rather involved procedure.
Accordingly, it is desired to provide a multifunction electronic analog watch which is applicable to a large diversity of watch functions and designs while ensuring efficiency in design and manufacture.